Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/761

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1870.]
GUNN—FOREST-BED AND CHILLESFORD CLAY.
551

described by Mr. Codrington on the slope between Canterbury and Herne Bay as indicative of the presence of a large river. He agreed with the author in considering that the white gravel was produced by the decolorization of the red; and remarked that it was unusual to find angular gravels of thoroughly marine type.

Mr. C. Moore remarked that the gravels and brick-earths from Salisbury westward are all of freshwater origin, and contain the remains of frogs in great abundance, together with freshwater shells, bones of Arvicolæ, &c.

Sir Charles Lyell was inclined to ascribe the formation of the gravels described to the sudden melting of snow in great quantities. He referred to the presence of sarsen-stones as indicating that there was force enough to carry large masses.

Prof. Ramsay referred to the great denudation of Eocene strata which must have taken place before the present form of the land was produced, as implying an immense amount of river-action, the immediate results of which are now masked by the modifications produced by subsequent subaerial changes of more limited extent. He maintained that the finding of flint implements at various elevationsonly rarely furnished direct evidence of change in the relative level of sea and land.

Mr. Codrington, in reply, stated that the gravels were not valley-gravels such as those mentioned by Mr. Moore. He did not see how glacial action could have spread the gravels over flat tablelands.


2. On the relative Position of the Forest-bed and the Chillesford Clay in Norfolk and Suffolk, and on the real Position of the Forest-bed. By the Rev. John Gunn, M.A., F.G.S.

At a meeting of the Geological Society, held May 20th, 1868, I stated, in opposition to the view entertained by Mr. Prestwich of the Forest-bed being placed above the Chillesford clay, that I had seen it at Easton Bavent, in Suffolk, upon the beach, at a lower level than the Chillesford clay in the cliff, and also that I had seen it at Kessingland and Pakefield, on the beach and at the foot of the cliff, underlying the Chillesford clay.

I have visited these places several times since; and a fall of the cliffs and the partial clearing away of the beach at Kessingland have exposed the strata in the following ascending order:—The Forest-bed on the beach; the freshwater Unio-bed, similar to those at Mundesley and Runton; the Fluvio-marine bed; the Marine (including the Chillesford clay, both the blue-laminated below and the brown-laminated above); the sands and gravels which contain the Tellina balthica crag at Wroxham Weybourne; and the Glacial series, which, as it does not enter into the present inquiry, I have not particularized.

The Forest-bed at Kessingland and the adjoining parish of Pake-